org.w3c.dom.traversal.NodeIterator Maven / Gradle / Ivy

/*
 * Copyright (c) 2000 World Wide Web Consortium,
 * (Massachusetts Institute of Technology, Institut National de
 * Recherche en Informatique et en Automatique, Keio University). All
 * Rights Reserved. This program is distributed under the W3C's Software
 * Intellectual Property License. This program is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even
 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 * PURPOSE.
 * See W3C License http://www.w3.org/Consortium/Legal/ for more details.
 */

package org.w3c.dom.traversal;

import org.w3c.dom.DOMException;
import org.w3c.dom.Node;

/**
 * NodeIterators are used to step through a set of nodes, e.g.
 * the set of nodes in a NodeList, the document subtree
 * governed by a particular Node, the results of a query, or
 * any other set of nodes. The set of nodes to be iterated is determined by
 * the implementation of the NodeIterator. DOM Level 2
 * specifies a single NodeIterator implementation for
 * document-order traversal of a document subtree. Instances of these
 * NodeIterators are created by calling
 * DocumentTraversal.createNodeIterator().
 * See also the Document Object Model (DOM) Level 2 Traversal and Range Specification.
 * @since DOM Level 2
 *
 * @hide
 */
public interface NodeIterator {
    /**
     * The root node of the NodeIterator, as specified when it
     * was created.
     */
    public Node getRoot();

    /**
     * This attribute determines which node types are presented via the
     * NodeIterator. The available set of constants is defined
     * in the NodeFilter interface.  Nodes not accepted by
     * whatToShow will be skipped, but their children may still
     * be considered. Note that this skip takes precedence over the filter,
     * if any.
     */
    public int getWhatToShow();

    /**
     * The NodeFilter used to screen nodes.
     */
    public NodeFilter getFilter();

    /**
     *  The value of this flag determines whether the children of entity
     * reference nodes are visible to the NodeIterator. If
     * false, these children  and their descendants will be rejected. Note
     * that this rejection takes precedence over whatToShow and
     * the filter. Also note that this is currently the only situation where
     * NodeIterators may reject a complete subtree rather than
     * skipping individual nodes.
     * 

     * 
 To produce a view of the document that has entity references
     * expanded and does not expose the entity reference node itself, use
     * the whatToShow flags to hide the entity reference node
     * and set expandEntityReferences to true when creating the
     * NodeIterator. To produce a view of the document that has
     * entity reference nodes but no entity expansion, use the
     * whatToShow flags to show the entity reference node and
     * set expandEntityReferences to false.
     */
    public boolean getExpandEntityReferences();

    /**
     * Returns the next node in the set and advances the position of the
     * NodeIterator in the set. After a
     * NodeIterator is created, the first call to
     * nextNode() returns the first node in the set.
     * @return The next Node in the set being iterated over, or
     *   null if there are no more members in that set.
     * @exception DOMException
     *   INVALID_STATE_ERR: Raised if this method is called after the
     *   detach method was invoked.
     */
    public Node nextNode()
                         throws DOMException;

    /**
     * Returns the previous node in the set and moves the position of the
     * NodeIterator backwards in the set.
     * @return The previous Node in the set being iterated over,
     *   or null if there are no more members in that set.
     * @exception DOMException
     *   INVALID_STATE_ERR: Raised if this method is called after the
     *   detach method was invoked.
     */
    public Node previousNode()
                             throws DOMException;

    /**
     * Detaches the NodeIterator from the set which it iterated
     * over, releasing any computational resources and placing the
     * NodeIterator in the INVALID state. After
     * detach has been invoked, calls to nextNode
     * or previousNode will raise the exception
     * INVALID_STATE_ERR.
     */
    public void detach();

}